1. Field of the Invention
The invention relates to an apparatus for placing cuttings of plants in a cultivation medium. The invention further relates to a method of placing cuttings of plants in a cultivation medium as well as to a computer readable medium having computer readable instructions stored thereon for performing, when executed by a processor, such a method. The invention also relates to a cutting holding unit for planting cuttings in a cultivation medium. Furthermore, the invention relates to an apparatus for placing cuttings of plants in a cultivation medium comprising such cutting holding unit. Finally, the invention relates to a method of placing cuttings of plants in a cultivation unit using such a cutting holding unit.
2. Description of the Related Art
Nowadays, placing plant cuttings in a cultivation medium is often still done manually. Besides being time consuming, each individual person plants the cuttings in a slightly different way. Furthermore, the position and orientation of the placed cuttings may vary widely as well. As a result, besides being expensive, the propagation success rate of the cuttings is relatively unreliable.
International application WO03/022034 describes a method and apparatus for collecting cuttings from a conveyor belt and placing these cuttings in pots. The apparatus includes a pick and place tool for picking and placing plant cuttings. The tool includes an array of actuable pick-up means for picking up the cuttings and retaining these cuttings with a predetermined orientation relative to the tool. The tool furthermore comprises an array of elongated means for providing indentations in the pots. The method and apparatus provide an automatic method for picking up cuttings and placing these cuttings in pots.
However, the method and apparatus described in WO03/022034 have several disadvantages. For example, the apparatus and method described in WO03/022034 lead to a cutting placement having insufficient uniformity. Although the cuttings are said to be picked up with a predetermined orientation relative to the tool, the sequential picking of adjacent cuttings may cause the orientation of the picked cuttings with respect to the tool to change due to interaction with each other, in particular during the picking process. As a result, some cuttings are placed into the pots with an orientation different from the predetermined orientation, which results in a poorly placed cutting.
Furthermore, the arrangement and functionality of the pick and place tool causes the apparatus to operate with a limited throughput, i.e. the number of cuttings that can be placed within a specific period of time is limited.
European patent application 1829446 describes an assembly for placing cuttings in plant plugs in which individual cuttings are gripped by one of the arms of a rotating device by means of under-pressure. The cuttings are then transferred to a belt provided with grippers. This transfer movement takes place continually and in a rotating manner.
However, the assembly described in EP1829446 has several disadvantages. First, the use of a rotating device for picking individual cuttings occupies a lot of space. Furthermore, the throughput of the assembly is sensitive to logistics failure. The cuttings need to be supplied individually with a spacing between subsequent cuttings that is between very strict boundaries. For example, if the subsequent cuttings are supplied to close together, either one of the cuttings is not processed, or the rotating speed of the rotating device should be adapted, i.e. increased, to allow pick up of both cuttings. The first option would decrease the throughput, whereas the second option causes the control of the rotating device to be complex.